Steven M. Weisberg

Variations in Cognitive Maps: Understanding Individual Differences in Navigation

There are marked individual differences in the formation of cognitive maps both in the real world and in virtual environments (VE; e.g., Blajenkova, Motes, & Kozhevnikov, 2005; Chai & Jacobs, 2010; Ishikawa & Montello, 2006; Wen, Ishikawa, & Sato, 2011). These differences, however, are poorly understood and can be difficult to assess except by self-report methods. VEs offer an opportunity to collect objective data in environments that can be controlled and standardized. In this study, we designed a VE consisting of buildings arrayed along 2 separated routes, allowing for differentiation of between-route and within-route representation. Performance on a pointing task and a model-building task correlated with self-reported navigation ability. However, for participants with lower levels of between-route pointing, the Santa Barbara Sense of Direction scale (Hegarty, Richardson, Montello, Lovelace, & Subbiah, 2002) did not predict individual differences in accuracy when pointing to buildings within the same route. Thus, we confirm the existence of individual differences in the ability to construct a cognitive map of an environment, identify both the strengths and the potential weaknesses of self-report measures, and isolate a dimension that may help to characterize individual differences more completely. The VE designed for this study provides an objective behavioral measure of navigation ability that can be widely used as a research tool.

The Lay of the Land: Sensing and Representing Topography

Navigating, and studying spatial navigation, is difficult enough in two dimensions when maps and terrains are flat. Here we consider the capacity for human spatial navigation on sloped terrains, and how sloping terrain is depicted in 2D map representations, called topographic maps. First, we discuss research on how simple slopes are encoded and used for reorientation, and to learn spatial configurations. Next, we describe how slope is represented in topographic maps, and present an assessment (the Topographic Map Assessment), which can be administered to measure topographic map comprehension. Finally, we describe several approaches our lab has taken with the aim of improving topographic map comprehension, including gesture and analogy. The current research reveals a rich and complex picture of topographic map understanding, which likely involves perceptual expertise, strong spatial skills, and inferential logic.

Learning to interpret topographic maps: Understanding layered spatial information

Novices struggle to interpret maps that show information about continuous dimensions (typically latitude and longitude) layered with information that is inherently continuous but segmented categorically. An example is a topographic map, used in earth science disciplines as well as by hikers, emergency rescue operations, and other endeavors requiring knowledge of terrain. Successful comprehension requires understanding that continuous elevation information is categorically encoded using contour lines, as well as skill in visualizing the three-dimensional shape of the terrain from the contour lines. In Experiment 1, we investigated whether novices would benefit from pointing and tracing gestures that focus attention on contour lines and/or from three-dimensional shape gestures used in conjunction with three-dimensional models. Pointing and tracing facilitated understanding relative to text-only instruction as well as no instruction comparison groups, but shape gestures only helped understanding relative to the no instruction comparison group. Directing attention to the contour lines may help both in code breaking (seeing how the lines encode elevation) and in shape inference (seeing how the overall configuration of lines encodes shape). In Experiment 2, we varied the language paired with pointing and tracing gestures; key phrases focused either on elevation information or on visualizing shape. Participants did better on items regarding elevation when language highlighted elevation and better on items requiring shape when language highlighted shape. Thus, focusing attention using pointing and tracing gestures on contour lines may establish the foundation on which language can build to support learning.

Children's Use of Slope to Guide Navigation: Sex Differences Relate to Spontaneous Slope Perception

Recent findings show that human adults can use slope to guide spatial search, although men significantly outperform women. To examine the sex difference more closely, we tested school-age children in a similar paradigm. Over four trials, children (n = 110) were disoriented and asked to locate a hidden target when the floor of a square enclosure was flat (control condition), sloped (slope condition), or sloped with a “ball drop demonstration,” intended to make the slope more salient (ball drop condition). In the presence of the slope cue, children performed above chance, although boys significantly outperformed girls. Boys were also more likely to notice the slope, and spontaneous slope perception was key to using the slope cue.

A slippery directional slope: Individual differences in using slope as a directional cue

Navigators rely on many different types of cues to build representations of large-scale spaces. Sloped terrain is an important cue that has received recent attention in comparative and human spatial research. However, the studies to date have been unable to determine how directional slope information leads to more accurate spatial representations. Moreover, whereas some studies have shown that the inclusion of slope cues improves performance on spatial tasks across participants (Kelly, 2011; Restat, Steck, Mochnatzki, & Mallot, 2004), other research has suggested individual differences in the benefits of slope cues (Chai & Jacobs, 2010; Nardi, Newcombe, & Shipley, 2011). We sought to clarify the role of sloped terrain in improving the representation of large-scale environments. In Experiment 1, participants learned the layout of buildings in one of two desktop virtual environments: either a directionally sloped terrain or a completely flat one. Participants in the sloped environment outperformed those in the flat environment. However, participants used slope information as an additional cue, rather than as a preferred reference direction. In Experiment 2, the two virtual environments were again either flat or sloped, but we increased the complexity of the relations between the slope and the path. In this experiment, better performance in the sloped environment was only seen for participants with good self-reported senses of direction. Taken together, the studies show that slope provides useful information for building environmental representations in simple cases, but that individual differences emerge in more complex situations. We suggest that good and bad navigators use different navigational strategies.

Up by upwest: Is slope like north?

Terrain slope can be used to encode the location of a goal. However, this directional information may be encoded using a conceptual north (i.e., invariantly with respect to the environment), or in an observer-relative fashion (i.e., varying depending on the direction one faces when learning the goal). This study examines which representation is used, whether the sensory modality in which slope is encoded (visual, kinaesthetic, or both) influences representations, and whether use of slope varies for men and women. In a square room, with a sloped floor explicitly pointed out as the only useful cue, participants encoded the corner in which a goal was hidden. Without direct sensory access to slope cues, participants used a dial to point to the goal. For each trial, the goal was hidden uphill or downhill, and the participants were informed whether they faced uphill or downhill when pointing. In support of observer-relative representations, participants pointed more accurately and quickly when facing concordantly with the hiding position. There was no effect of sensory modality, providing support for functional equivalence. Sex did not interact with the findings on modality or reference frame, but spatial measures correlated with success on the slope task differently for each sex.

Keeping track of where we are: Spatial working memory in navigation

ABSTRACT Spatial working memory (WM) seems to include two types of spatial information: locations and relations. However, this distinction has been based on small-scale tasks. Here, we used a virtual navigation paradigm to examine whether WM for locations and relations applies to the large-scale spatial world. We found that navigators who successfully learned two routes and also integrated them were superior at maintaining multiple locations and multiple relations in WM. However, over the entire spectrum of navigators, WM for spatial relations, but not locations, was specifically predictive of route integration performance. These results lend further support to the distinction between these two forms of spatial WM and point to their critical role in individual differences in navigation proficiency.

Sex differences and errors in the use of terrain slope for navigation

Unlike most of the spatial cues that have received attention, a sloping terrain can be perceived by multimodal sensory inputs (vision, balance, and kinesthesia), making it potentially very salient for navigation. Furthermore, a homogeneous slope can be used like a compass to identify directions (e.g., uphill, downhill, and sideways), but not to determine distances. We briefly review recent evidence on navigation with slope, emphasizing two main findings. On the one hand, we focus on the conspicuous sex difference found in the ability to localize a target in a square, tilted enclosure; this has emerged in human adults and children, and we suggest that it is related to lower awareness of the slope for females. On the other hand, we describe the general pattern of errors that arises when localizing the target during the task; these errors indicate the use of a bi-coordinate representation of the slope. Limitations and ideas for future studies are proposed.

When gestures show us the way: Co-thought gestures selectively facilitate navigation and spatial memory

ABSTRACT How does gesturing during route learning relate to subsequent spatial performance? We examined the relationship between gestures produced spontaneously while studying route directions and spatial representations of the navigated environment. Participants studied route directions, then navigated those routes from memory in a virtual environment, and finally had their memory of the environment assessed. We found that, for navigators with low spatial perspective-taking performance on the Spatial Orientation Test, more gesturing from a survey perspective predicted more accurate memory following navigation. Thus, co-thought gestures accompanying route learning relate to performance selectively, depending on the gesturers’ spatial ability and the perspective of their gestures. Survey gestures may help some individuals visualize an overall route that they can retain in memory.

Charting the development of cognitive mapping

Developmental research beginning in the 1970s has suggested that childrens ability to form cognitive maps reaches adult levels during early adolescence. However, this research has used a variety of testing procedures, often in real-world environments, which have been difficult to share widely across labs and to use to probe components of mapping, individual differences in success, and possible mechanisms of development and reasons for individual variation. In this study, we charted the development of cognitive mapping using a virtual navigation paradigm, Silcton, that allows for testing samples of substantial size in a uniform way and in which adults show marked individual differences in the formation of accurate route representations and/or in route integration. The current study tested children aged between 8 and 16 years. In terms of components of normative development, childrens performance reached adult levels of proficiency at around age 12, but route representation progressed significantly more quickly than route integration. In terms of individual differences, by age 12 children could be grouped into the same three categories evident in adults: imprecise navigators (who form only imprecise ideas of routes), non-integrators (who represent routes more accurately but are imprecise in relating two routes), and integrators (who relate the two routes and, thus, form cognitive maps). Thus, individual differences likely originate during childhood. In terms of correlates, perspective-taking skills predicted navigation performance better than mental rotation skills, in accord with the view that perspective taking operates on extrinsic spatial representations, whereas mental rotation taps intrinsic spatial representations.